The long-term goal of this work is to learn how mammalian cells produce levels of m-RNA appropriate to their specialized functions. This will be accomplished by investigating the roles of basal and activated transcription factors in setting m-RNA levels. The results will contribute to learning how mutant factors lead to inappropriate m-RNA production, a component of the imbalances that are associated with cancer. The specific aims of this project are: 1. To learn the relationships among the critical ATP-dependent steps occurring at polymerase II promoters. These include start site DNA opening, polymerase phosphorylation and transcription initiation. 2. To learn what mechanistic features limit the ability to transcribe a polymerase II promoter. This includes learning the roles of specific factors and elements in setting both the rate and efficiency of transcription initiation and re-initiation. 3. To learn to what extent the principles discovered in aims l and 2 might be generally applicable. This includes comparing selected promoters, with emphasis on TATA versus initiator and basal versus activated.